Add MD5 computation to Esp and add request header with MD5 hash of the running...

Add MD5 computation to Esp and add request header with MD5 hash of the running sketch to HTTPUpdate (#2176)

cores/esp32/Esp.cpp

@@ -30,6 +30,7 @@
 extern "C" {
 #include <esp_image_format.h>
 }
+#include <MD5Builder.h>
 
 /**
  * User-defined Literals
@@ -158,9 +159,9 @@ static uint32_t sketchSize(sketchSize_t response) {
     data.start_addr = running_pos.offset;
     esp_image_verify(ESP_IMAGE_VERIFY, &running_pos, &data);
     if (response) {
-    return running_pos.size - data.image_len;
+        return running_pos.size - data.image_len;
     } else {
-    return data.image_len;
+        return data.image_len;
     }
 }
     
@@ -168,6 +169,46 @@ uint32_t EspClass::getSketchSize () {
     return sketchSize(SKETCH_SIZE_TOTAL);
 }
 
+String EspClass::getSketchMD5()
+{
+    static String result;
+    if (result.length()) {
+        return result;
+    }
+    uint32_t lengthLeft = getSketchSize();
+
+    const esp_partition_t *running = esp_ota_get_running_partition();
+    if (!running) {
+        log_e("Partition could not be found");
+
+        return String();
+    }
+    const size_t bufSize = SPI_FLASH_SEC_SIZE;
+    std::unique_ptr<uint8_t[]> buf(new uint8_t[bufSize]);
+    uint32_t offset = 0;
+    if(!buf.get()) {
+        log_e("Not enough memory to allocate buffer");
+
+        return String();
+    }
+    MD5Builder md5;
+    md5.begin();
+    while( lengthLeft > 0) {
+        size_t readBytes = (lengthLeft < bufSize) ? lengthLeft : bufSize;
+        if (!ESP.flashRead(running->address + offset, reinterpret_cast<uint32_t*>(buf.get()), (readBytes + 3) & ~3)) {
+            log_e("Could not read buffer from flash");
+
+            return String();
+        }
+        md5.add(buf.get(), readBytes);
+        lengthLeft -= readBytes;
+        offset += readBytes;
+    }
+    md5.calculate();
+    result = md5.toString();
+    return result;
+}
+
 uint32_t EspClass::getFreeSketchSpace () {
     const esp_partition_t* _partition = esp_ota_get_next_update_partition(NULL);
     if(!_partition){

cores/esp32/Esp.h

@@ -90,6 +90,7 @@ public:
     FlashMode_t magicFlashChipMode(uint8_t byte);
 
     uint32_t getSketchSize();
+    String getSketchMD5();
     uint32_t getFreeSketchSpace();
 
     bool flashEraseSector(uint32_t sector);

libraries/HTTPUpdate/src/HTTPUpdate.cpp

@@ -181,8 +181,11 @@ HTTPUpdateResult HTTPUpdate::handleUpdate(HTTPClient& http, const String& curren
     http.addHeader("x-ESP32-AP-MAC", WiFi.softAPmacAddress());
     http.addHeader("x-ESP32-free-space", String(ESP.getFreeSketchSpace()));
     http.addHeader("x-ESP32-sketch-size", String(ESP.getSketchSize()));
-// To do    http.addHeader("x-ESP32-sketch-md5", String(ESP.getSketchMD5()));
-    // Sketch MD5 is not supported by the core, but SHA256 is, so add a SHA256 instead
+    String sketchMD5 = ESP.getSketchMD5();
+    if(sketchMD5.length() != 0) {
+        http.addHeader("x-ESP32-sketch-md5", sketchMD5);
+    }
+    // Add also a SHA256
     String sketchSHA256 = getSketchSHA256();
     if(sketchSHA256.length() != 0) {
       http.addHeader("x-ESP32-sketch-sha256", sketchSHA256);